Embryo formation

Discussion in 'Human Science' started by timojin, Jul 2, 2016.

  1. timojin Valued Senior Member

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    At what point in time the spinal cord and brain start to form
     
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  3. DaveC426913 Valued Senior Member

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  5. timojin Valued Senior Member

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    It is interesting the development of the brain and its detail complicated arrangement, You get to think to continue development of the brain, chemical raw material is necessary to have present. In order to alter the process some alternate or disproportionate raw material must be introduced and that would cause an alternate outcome of the embryo ?
     
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  7. Daecon Kiwi fruit Valued Senior Member

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    You mean if the mother wasn't getting sufficient nutrition?
     
  8. timojin Valued Senior Member

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    I understand the mother is the source of nutrition , but also is important if the right chemicals ( amino acids and others ) out body can not produce all the 22 amino acids there are some essential that our body does not produce
     
  9. Daecon Kiwi fruit Valued Senior Member

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    Can you elaborate on that?
     
  10. Fraggle Rocker Staff Member

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    There are nine amino acids that the human physiology cannot synthesize from other amino acids. Therefore, they must be provided in food.
    • phenylalanine
    • valine
    • threonine
    • tryptophan
    • methionine
    • leucine
    • isoleucine
    • lysine
    • histidine
    Fortunately, every one of these is readily available in common food sources. Obviously, mother's milk provides them all, assuming that the mother has a reasonably well-functioning metabolism and eats a reasonable diet.
     
  11. Daecon Kiwi fruit Valued Senior Member

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    Thanks for that. Are humans unique in being unable to synthesize those amino acids? I wonder if it's a similar situation to Vitamin C, a potentially harmful mutation that didn't have any selection pressure against it due to available food, and so it persisted into the gene pool?
     
  12. timojin Valued Senior Member

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    There is a writing I forgot the time period, Sailors that were long time on a ship had blisters on their lips , the cure was vitamin C , that will imply we do not produce vitamin C
     
  13. DaveC426913 Valued Senior Member

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    Lack of vitamin C will produce a lot worse than blisters. Scurvy will kill you, slowly and painfully. Staving off scurvy resulted in the English sailors geting the nickname limeys!

    But back on-point.

    Yes, malnutrition in the mother will result in hampered growth in the foetus. Fortunately (or unfortunately, depending on which end of the umbilical you are at) the developing foetus tends to get "first-dibs" at critical nutrients - it will essentially take what it needs and leave what's left for mother. Severe malnutrition, on the other hand, means there isn't enough for either mother or foetus.
     
  14. timojin Valued Senior Member

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    Very good details I could not remember of hand the word Scurvy . The question was do we produce vitamin C , but you did a good job
     
  15. Fraggle Rocker Staff Member

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    The reasons that our metabolism is unable to synthesize these amino acids are:
    • 1. They are rather widely available in our food sources.
    • 2. We don't need a very large amount of any of them.
    They are typically referred to as the "essential amino acids," but this is an unfortunate coinage of a phrase. It makes it seem like they are the most important amino acids in our diets, when in fact the truth is just about the opposite. We need them in such small quantities that it's very difficult to become deficient in them. You'd have to be on some ridiculously weird diet, or to get lost in some remote place where none of the plants that provide these nutrients can be found.
     
  16. iceaura Valued Senior Member

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    Most people in North America are deficient in vitamin C, to some degree. Almost everyone in NA who doesn't take deliberate steps to increase their intake of C - by searching out high C foods on purpose, most of them transported long distances from other regions, or by artificially supplementing their diets with manufactured chemicals - is seriously deficient.

    Likewise vitamin D.

    Human metabolism did not evolve under the pressures and influences of temperate zone climate and ecology, or inland climate and ecology. The adaptations include dietary.
     
    Last edited: Jul 5, 2016
  17. timojin Valued Senior Member

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    The main outcome measure was nitrogen balance. Rose noted that the symptoms of nervousness, exhaustion, and dizziness were encountered to a greater or lesser extent whenever human subjects were deprived of an essential amino acid
     
  18. exchemist Valued Senior Member

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    This about Vitamin C in N America sounds unlikely to me. What is your source for this claim?
     

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